1. Field of the Invention
The present invention broadly relates to infeeding and outfeeding substantially flat products arranged in an imbricated or shingled formation and, more specifically, pertains to a new and improved apparatus for selectively or alternatively transferring flexible flat products, especially printed products such as newspapers, magazines and the like, from an imbricated formation or array conveyed along a first conveying path onto a second conveying path.
Generally speaking, the apparatus of the present invention is of the type comprising a first conveyor defining the first conveying path, a second conveyor defining the second conveying path, and a transfer or carry-over conveyor provided between the first conveyor and the second conveyor, the transfer or carry-over conveyor having a conveying entrance facing the first conveyor and a stationary conveying exit facing the second conveyor. The transfer or carry-over conveyor comprises two conveying arms arranged in tandem, pivotably connected with each other and structured as a belt conveyor. The two conveying arms constitute a first conveying arm and a second conveying arm. The first conveying arm, having a conveying-active end, is located directly upstream of the second conveyor and stationarily pivotably mounted in the region of the conveying-active end. There is also provided a driving arrangement, by means of which both conveying arms are pivotable in knee-like manner, in order to take the aforesaid conveying entrance provided at the free end of the second conveying arm to a working position, disposed in neighboring relationship to the first conveyor, for the purpose of separating printed products from the imbricated formation, and to take the conveying entrance to a withdrawal position remote from the first conveyor for the purpose of terminating the separation of printed products from the imbricated formation. Furthermore, pressing means, having at least one endless revolving pressing or hugger belt or band, are allocated to the two conveying arms for the purpose of forming a conveying gap in conjunction with the two conveying arms.
2. Discussion of the Background
Such an apparatus is known, for example, from U.S. Pat. No. 2,815,949, granted Dec. 10, 1957. The apparatus disclosed therein comprises two conveying arms which are pivotably connected with each other and provided with respective endless revolving tapes or belts guided around rolls, which are mounted at a common shaft provided at the pivot connection of the two conveying arms. The first conveying arm is stationarily mounted at its conveying-active end which is remote from the second conveying arm. The second conveying arm is guided at its free end in a curved slide. The operating arm of an air cylinder anchored to a bottom support is joined to the aforesaid common shaft at which the rolls are supported, so that by lowering the shaft, the free end of the second conveying arm, i.e. the conveying entrance with a pick-up nose in the form of a scoop, is brought into the conveying path of a first belt conveyor, and the printed products, inbound in an imbricated formation on this first belt conveyor, are fed to a belt conveyor arranged downstream of the transfer conveyor formed by the two conveying arms. Upon raising the shaft by means of the operating arm of the air cylinder, the transfer conveyor is bent in a knee-like manner and the conveying entrance is retracted from the conveying region of the first belt conveyor. The inbound printed products reposing on the first belt conveyor are again further conveyed by the latter. Above the two conveying arms, there are arranged pressing means comprising two pivotably connected pressing elements, which are structured in a conveyor belt-like manner and have respective endless revolving pressing tapes or belts. These pressing tapes or belts, forming a conveying gap in conjunction with the respective endless revolving tapes or belts of the conveying arms, are guided about rolls having a common axis located at the pivot connection of the two pressing elements. A rod slidably supported by both a pivoted guide and an assembly mounting the rolls having the common axis, is joined to the aforesaid common shaft from above. This rod, together with a spring assembly joined thereto, is provided for cooperation between the pairs of tapes of the transfer or carry-over conveyor. Side members supporting the rolls of the conveying arms and supporting members for mounting the rolls of the pressing elements are joined by means of angularly disposed links.
This known construction of a transfer or carry-over conveyor is disadvantageous in that the conveying gap varies according to the pivoting position of the conveying arms not only as to its position relative to the conveying arms, but also with respect to its height or gap clearance. As a result, the printed products can be displaced with respect to their mutual position during the pivoting movement of the conveying arms such that further cyclical or cadenced processing of the printed products is rendered impossible in most cases. Furthermore, very thin printed products or the like are not correctly held in the conveying gap of this known transfer conveyor. However, since the products designated as signatures are supplied alternatively to two so-called jogger boxes, it is conceivable that the mutual position of the signatures outbound to the one or other jogger box is of no account.
An apparatus serving essentially the same purpose but relatively different in construction and design is known from, for example, German Patent Application No. 2,820,957, published Dec. 7, 1978. This prior art construction comprises a first conveyor provided with two belt conveyors arranged in tandem and elevationally offset or staggered for transporting printed products arranged in a imbricated array along a first conveying path. Between this first conveying path and a second conveying path, there is provided a transfer or carry-over conveyor for the purpose of separating individually or in groups the printed products conveyed in the imbricated array over the step formed by the two elevationally offset belt conveyors, and for the purpose of feeding the separated product or products to the second conveying path. As viewed in the conveying direction, the transfer or carry-over conveyor, which is arranged downstream of the aforesaid step and conveys the separated product or products in an inclinedly upward direction, comprises two stationary guide rods and a carriage which is telescopingly displaceable thereat. Two conveyor belts, the contiguous conveying-active runs of which form a conveying gap and extend from rolls arranged at the bottom end of the carriage to rolls mounted at the upper end of the stationary guide rods, are guided with their return runs around further rolls provided at the bottom end of the stationary guide rods and at the upper end of the carriage, in order to compensate for variations of the length of the conveying-active runs during displacement of the carriage. At the lower end of the carriage there is pivotably mounted a tongue or blade directed towards the step. When the carriage is in its lower end position and the tongue or blade is upwardly pivoted, the imbricated formation of printed products is conveyed under the transfer or carry-over conveyor and along the first conveying path. On the other hand, when the tongue or blade is pivoted downwardly, it deflects from below the printed product conveyed over the step and conducts the printed product to the conveying gap of the transfer or carry-over conveyor.
As soon as the last printed product to be fed onto the second conveying path has been deflected and seized by the conveying gap, the carriage is upwardly retracted and the tongue or blade is subsequently pivoted in the upward direction for the purpose of separating this last printed product from the next following or trailing printed product. The speed of the upward movement of the carriage is thereby lower than the revolving speed of the conveyor belts. This revolving speed, especially in the case of separation of printed products in groups from the imbricated formation, is equal to the conveying speed of the first conveyor. As a result, the two printed products to be separated or detached from one another are conveyed at very much the same speed, and the next following or trailing printed product, which is gripped from below by the preceding or leading printed product held by the two conveyor belts, is raised in the upward direction and entrained by virtue of friction or, as the case may be, displaced or shifted out of its position with respect to the other printed products arranged in the imbricated formation.